How green is Building’s building? | Features

How Ludgate House could get a C
		kg CO² per m² floor area
		Heating	Cooling	Auxiliary	Lighting	Hot water	Total	Rating
	Notional building	7.8	23.2	16.5	21.0	2.8	71.3	100%	C
1	Ludgate House – base case	25.5	41.2	27.2	20.4	2.0	116.3	162%	E
2	Improving U-value of glazing from 4 to 2.8	20.9	44.3	27.2	20.4	2.0	114.8	160%	E
3	Boiler efficiency improved from 0.65 to 0.7	18.6	44.3	27.2	20.4	1.8	112.3	156%	E
4	Wall U-value improved from 0.6 to 0.55	18.1	44.4	27.2	20.4	1.8	111.9	156%	E
5	Air permeability from 10 to 5 m3/h/m2	12.0	44.7	27.2	20.4	1.8	106.1	147%	E
6	System air-leakage tests passed	10.3	38.6	23.1	20.4	1.8	94.1	131%	D
7	System energy metering with alarms	9.9	36.6	22.0	20.4	1.8	90.7	126%	D
8	Lighting improved to HF triphosphor	10.4	34.4	22.0	16.0	1.8	84.6	118%	D
9	Use of air-extracting luminaires	10.5	33.6	22.0	16.0	1.8	83.9	117%	D
10	Cooling efficiency improved from 2.5 to 3	10.5	22.4	22.0	16.0	1.8	72.7	101%	C
11	Specific fan power improved from 3 to 2	10.9	21.1	16.8	16.0	1.8	66.6	93%	C